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Fuel gauge issue- 2007 R12RT

I just put some HID's in my 2007 r1200rt. This involves taking boith sides of the top tupper ware off. When I put it back together, it shows Im out of fuel. I'm about a gallon from being full. I pulled and reseated the connectors on the top right of the tank and the issue remains. Is there a "reset" or something? Anything else to check? Thanks for any help guys..

It sounds like the fuel strip is bad. If it is, has nothing to do with the work you just did on headlights.

If the yellow warning light is on and the fuel icon is flashing it is definately the fuel strip. If only one of these is on it could still be the fuel strip. I have also had fuel strip failure with only the fuel gage showing empty. It also happened at the dealer on pickup from a service. I have gone through five or six fuel strips to date on my 08 RT.

Jack

"All my life I wanted to be somebody. Now I realize I should have been more specific."

It sounds like the fuel strip is bad. If it is, has nothing to do with the work you just did on headlights.

If the yellow warning light is on and the fuel icon is flashing it is definately the fuel strip. If only one of these is on it could still be the fuel strip. I have also had fuel strip failure with only the fuel gage showing empty. It also happened at the dealer on pickup from a service. I have gone through five or six fuel strips to date on my 08 RT.

Jack

"All my life I wanted to be somebody. Now I realize I should have been more specific."

Is there a "home way" to dianose that? I know you have to take it to the dealer to replace it. Can I ohm the wires or something? And they are both blinking... The yellow light and the flashing fuel pump..

The reason I'm asking - I can imagine the possibility that inexpensive ones with cheaply built ballasts/ignitors might let some high-voltage pulse back through the connection to the ZFE module (that controls the lights.)

There have been instances of some bikes failing the fuel strip repeatedly at very short intervals, and in those cases I really think something besides bad fuel strips is at work (ie - something is causing them to fail - something electronic..)

I bought the HIDs from "1offmotorsports.com", appear to be a quality product.

They connect to the existing headlight bulb connectors.

I mounted them up in the plastic, and the included mount attaches them right where the bike speakers go, which I don't have. Convenient. ----

I looked up the Schematic in my haynes manual and it shows the fuel strip. It appears that between pins 1 and 4 there is some sort of inductor or heater element. Pins 2 to 3 appears to be a variable resistance.

On power up the bike supplies 9.5 vdc on pins 1-4 to the fuel strip. After about 10 seconds the voltage drops to 1.5 vdc.

Pins 2-3 on OLD fuel strip measures 20.4 Kohm AFTER the bike has been shut off for at least a half hour. Otherwise it shows an OPEN. In otherwords, if I have a 20 k reading and then cycle power the strip goes OPEN on pins 2-3.

Pins 2-3 on the NEW strip show 2.37 Kohm. a factor of 10 difference.

Conclusion: I assume the bike supplies voltage to heat the fuel strip and likewise changes the resistance per fuel level. The resistance is broke on my strip. I'll be putting the new strip in a few days (once I get over my cold) "disassemble" the old strip and post it here.

I tried fooling the bike by putting various resistances across pins 2-3 when powered up but didn't work. I'll put a jumper in when I install the NEW strip and measure the actual resistance with the bike powered....... hopefully.

Only other thought I have is that the placing of the HID high voltage wiring may have caused coupling into the wiring and affecting(damaging) the fuel sensor. Which means pulling the instrument plastic off again... sigh....

Thanks for the detailed readout on Ohm readings. I'm hoping to have another dead fuel strip in hand in a few days and it will be interesting to compare the measurements.

You're correct on how the system works - it's a Wheatstone-bridge being used for temperature sensing. The current through the heater warms the sensor, then the current passing through higher resistance element is measured and it changes with how much of that element is submerged in the fuel.. Pretty basic device (we used to make the same sort of thing back at Bell Labs for measuring the level of liquid nitrogen in a dewar..)

I had another one that I disassembled - at the dealers - so I didn't have a chance to take measurements - but there was no visible damage to the actual elements. They appear to be evaporated metallic traces on a flexible clear plastic strip that is held in a plastic housing.

Please let us know what'cha see when you get yours apart.

And your thinking on the high-voltage trigger pulse coupling to the wiring (probably for the ZFE) is along the same lines as mine. Might it be possible to put some braided shielding over the HV wiring going to the capsule and ground that?